A fungus causes a disease of bean plants. Scientists placed 30 healthy bean plants in each of three sealed enclosures. Air was pumped into each enclosure at the same rate. A fine filter was used to remove fungal spores from some of the air.
After 14 days, the scientists recorded the number of plants that had developed the disease.
| Source of air | Air filtered before entering the enclosure | Number of plants that developed the disease |
|---|---|---|
| room containing infected plants | no | 24 |
| room containing infected plants | yes | 3 |
| room containing healthy plants | no | 2 |
Explain what the results show about how the disease is transmitted and how removing the infected plants from the source room would affect the number of plants developing the disease.
112 exam-style questions on Edexcel GCSE Biology 5.1 Health and communicable disease, covering 5.1.1 Communicable and non-communicable diseases, 5.1.2 Disease susceptibility interactions, 5.1.3 Pathogens as disease-causing organisms, 5.1.4 Common infections, 5.1.5 Spread and prevention of pathogens, 5.1.6 Lifecycle of a virus, and 5.1.7 Spread and prevention of STIs. Each one has a worked solution and a mark scheme showing where the marks go.